[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: Re: Discovery Project: Which Mission Next?

on 9/4/00 11:55 PM, Tony Langdon at tlangdon@atctraining.com.au wrote:

>> What I think we need is something like about a 1 second frame
>> rate.  This
>> would only take 12 dB more than FM and about 250 KHz instead
>> of the 6 MHz
>> for FSTV..  But rather than inventing another wheel, I suspect the mor
>> universal approach will be just to have a high data rate digital
>> transponsder, and then JPIG images can be exchanged just as
>> easliy...  ANd
>> with the possible compression, this will be far more effecient thatn
>> either FSTV or FAST-FM SSTV....
>> In any case, what would be a good target?  1 Image a second?
> Well, with digital technology, it has already been proven that a useable (~
> 1fps) video channel can be obtained on a data stream < 30kbps.  Many people
> do it everyday on the Internet!  So, it's not unreasonable to expect a
> moderate bandwidth video  link vis satellite.  At 30kbps, this is within
> current bandwidths and modem technology.

I believe that P3D has some really fast digital capabilities.  With 64K, you
certainly can get a decent compressed frame rate.  If we were ever able to
get up to a 300 K rate, you could get a full frame video stream.

DEFINITELY something to think about, but Bob is also right - NOT for a LEO!



Jon Ogden
NA9D (ex: KE9NA)



"A life lived in fear is a life half lived."

Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org